An electrical connection box mounted on a vehicle has various structures according to a vehicle type. However, for example, an electrical connection box has a structure including a block on which electrical components are mounted, a frame which accommodates the block, and a cover such as an upper cover, a lower cover, or a side cover which covers the block and the frame. The block or the frame is generally a molded article made of an insulating resin. In addition to bus bars connected to an external power supply, electrical components, such as various relays, fuses and fusible links, are mounted on the block. A cavity for accommodating the block is formed in the frame. Also, a relief terminal may be provided in the bus bar so as to supply power from an external power supply by using a booster cable at the time of battery exhaustion. A structure of an electrical connection box including the relief terminal is suggested (e.g., refer to Patent Literatures 1 and 2).
The relief terminal described in Patent Literature 1 is provided in a type of (similar) power supply box of the electrical connection box. As illustrated in FIG. 8, the electrical connection box includes a base 101, a main cover 102, and a bus bar 103 mounted on the base 101. The relief terminal 104 is provided in a bus bar 103. Furthermore, an opening 105 exposing the relief terminal 104 to the outside is formed in the main cover 102, and a sub cover 106 covering the opening 105 and the relief terminal 104 is attached. A hinge shaft 107 provided in the sub cover 106 and a bearing 108 made of an arc piece provided in the main cover 102 are mutually latched. Therefore, the sub cover 106 is rotatably supported to the main cover 102 over a position covering the relief terminal 104 and a position exposing the relief terminal 104.
On the other hand, a relief terminal described in Patent Literature 2 is provided in an electrical connection box including a block and a frame as described above. As illustrated in FIG. 9, a bus bar 112 is mounted on a block 111, and the relief terminal 113 is provided to protrude from a hole section 114 of the block 111. Also, a terminal support plate 115 protruding from an edge portion of the hole section 114 is integrally formed in the block 111, and the relief terminal 113 is provided along the terminal support plate 115. The relief terminal 113 and the terminal support plate 115 are grasped together by a clamp of a booster cable, and it is configured to prevent the disengagement of the clamp. Also, the block constitutes a box body accommodated in a frame (not illustrated). A cavity accommodating the block and an opening passing through the relief terminal 113 and the terminal support plate 115 are formed in the frame.